If you're doing a documentary about a liar or a conman and you don't include any content critical of that liar or conman in your film, you aren't doing a documentary. The conman is using you as a medium to spread their message to an audience they wouldn't have access to otherwise.

By adopting Moyer's approach, you're essentially legitimizing the figure you're covering and making people more likely to follow them.

And Alex wants to exploit homeless people for his documentary.

If you're stupid, you can get away with putting this documentary up there. You're dumb. If you are putting quotes on screen, hanging them as, like, This is a big fucking deal. Knowing full well these were not said by anybody related to what's going on here. Then that goes over from being you're dumb to being this is on purpose.